These list of Linux commands will help you when you are working with the Terminal

A
  • alias:         Allows you to set aliases and view the current aliases.
  • awk:          Search for a pattern within a file
  • alien:         Converts .tgz and rpm's to .deb format.
B
  • banner:       Prints characters as a poster.
  • badblocks:  Searches a device for bad blocks.
  • biff:             Turns mail notification on and off.
  • bg:             Move a job running in the foreground to the background.
  • bzip2:         Used to compress and decompress files. Similar to gzip
C
  • cardctl:      Used to control PCMCIA cards.
  • cfdisk:        Used to partition a hard disk.
  • cp:             Copy
  • chattr:        Changes the attributes of a file or folder.
  • chroot:       Change the root directory for a command.
  • chmod:       Used to change permissions on a directory or file.
  • chown:       Used to change the owner of a file or directory.
  • chgrp:         Used to change the group a file belongs to.
  • clear:         Clears the screen
  • cpio:          Copies file.
  • cat:            Displays the content of a file
  • chpasswd:  Used to change a large number of passwords at once.
  • cd:             Changes directories.
  • chage:        Sets password aging parameters.
  • cal:             Displays a calendar.
  • cron:           Used to execute commands at a certain time.
  • crontab:       Allows you to view or edit the current cron jobs.
D
  • dselect:       A graphical front end for dpkg.
  • dpkg:          Installs packages on debain distro's.
  • date:           Prints current date to the screen
  • du:              Lists disk usage in a directory.
  • df:               Reports disk usage information. df -h
  • dmesg:        Used to view the kernel boot file.
  • dump:          Used for backing up.
E
  • edquota:       Sets quotas for specific users.
  • env:              Lists current environment variables.
F
  • fdisk:         Used to create/edit/delete partitions.
  • fsck:          Checks a file system for consistency.
  • fg:              Used to send jobs to the background.
  • fuser:         Checks to see what processes and users have open files.
  • find:           Searches for a file.
  • free:           Will show total memory, used memory, and free memory.
G
  • gcc:               Used to compile C, Assembler, and Preprocessed C source.
  • gpasswd:       Used to set a password for a group.
  • grep:              Used to search through a file for a specified pattern.
  • getty:             Set terminal type, modes, speed, and line discipline
  • groupadd:       Create new group account.
  • groupdel:        Deletes a group.
  • groupmod:      Used to modify a group.
  • groups:          Shows what groups a user is part of.
  • gunzip:          Uncompress files compressed by gzip.
H
  • head:         Displays the first 10 lines of a file to the screen.
  • hdparm:     Gets disk information.
  • history:      Lists recently executed commands.
  • host:          Used to get DNS info.
  • htpasswd:  Allows you to set usernames and passwords for your websever.
I
  • id:            Display information about yourself or another user.
  • insmod:    Installs modules.
  • init:          Used to change run levels.
  • isapnp:     Sets up ISA cards.
  • icmpinfo:   Intercept and interpret ICMP packets
J
  • jobs:       Used to show jobs running in the background.
  • join:        Join lines of two sorted.
K
  • kill:           Used to kill a process.
  • killall:        Kill processes by command name.
  • kernelcfg:  A graphical application configures Linux.
  • klogd:       Control which kernel messages.
L
  • linuxconf:    A command line GUI which lets you configure your linux
  • lpc:            Used to control a line printer.
  • lpq:            View the print spool queue.
  • lpr:             Send files to the printer spool queue.
  • ls:              Displays a directories contents.
  • ln:              Used to create hard and symbolic links.
  • less:          Display the contents of a file
  • locate:       Search for a file or directory.
  • ldd:            Shows what shared libraries a program is dependent on.
  • ldconfig:     Used to configure/view shared libraries.
  • last:           Lists logins and reboots.
  • lastlog:       Print the last login times for system accounts.
  • lsmod:        Lists loaded modules.
  • lsattr:         Lists the attributes for a file or folder.
  • logrotate:    Used to manipulate log files.
M
  • mount:      Used by itself, reports the currently mounted files.
  • modinfo:    Give info about the module.
  • modprobe: Queries modules.
  • man:         Displays the Man page for a given command.
  • mesg:       Used to allow/not allow 'write'.
  • manpath:   Attempts to determine the path to a man page.
  • mail:         Used to send and receive mail.
  • mkdir:       Make directory
  • mke2fs:     Used to format a partition with the Ext2 file system.
  • mv:           Move/Rename
  • merge:      Merge multiple files together.
  • more:        Lets you page through text one screen full at a time.
  • minicom:   Great utility for troublshooting a modem.
  • mkbootdisk: Used to make a boot disk.
N
  • ntsysv:     Used to select what services should automatically start.
  • nice:        Used to set process priorities.
  • nslookup: Used to get DNS info from name servers.
  • netstat:    Shows active sockets.
P
  • ps:             Displays current processes.
  • ping:           Used to test connectivity between two hosts.
  • pwd:           Present Working Directory
  • pwconv:       Used to set up the /etc/shadow file.
  • pnpdump:    Determines settings for existing ISA cards.
Q
  • quota:      Allows users to view their own disk quotas.
  • quotaon:   Turns on disk quotas for the system.
  • quotaoff:   Turns off disk quotas for the system.
R
  • repquota: Provides reports of disk usage for various users.
  • rmmod:   Removes modules.
  • rm:         Remove
  • rmdir:      Remove directory
  • rpm:        (RedHat flavors only)Used to install RPM's
  • rpcinfo:    Used to see what rpc services are available.
  • route:      Used to view/change routes between you and other hosts.
S

  • smbclient:     Used to connect to Windows shares or Samba.
  • smbadduser: Maps linux user names to Windows NT user names.
  • smbpasswd:  Used to update the smbpasswd file with new accounts.
  • set:               Used to read and write variables.
  • setquota:       Used to set disk quotas.
  • sort:              Sorts lines in a file by alphabetical order.
  • sndconfig:      Used to probe and configure a sound card.
  • su:                Change to Super User (root).
  • spell:             Checks for spelling errors in a file.
  • startx:           Start the X Server (GUI)
  • shutdown:      Shutdown machine
  • suspend:        Places a shell in the background.
  • showmount:   Shows mount information for an NFS server.
  • swapon:         Turns on the swapfile.
  • swapoff:         Turns off the swapfile.
T
  • testparm:    Used to troubleshoot Samba.
  • tar:             Used to compress multiple files.
  • timeconfig:  Used to set the timezone on your machine.
  • tac:            View a file from the last line up.
  • touch:        Creates an empty file.
  • tail:            Displays the last 10 lines of a file to the screen.
  • talk:           Used to chat with another user on the same machine.
  • tr:              Converts one set of characters to another.
  • traceroute:  Used to track the path a packet takes to a host.
  • top:            Shows information about the most CPU-intensive Apps.
U
  • useradd:     Add a user.
  • usermod:    Modify a user.
  • userdel:      Delete a user.
  • umount:      Removes a device from the filesystem.
  • updatedb:   Updates the locate database.
  • uname:       Determines OS name, version and machine name.
V
  • vmstat:     Lists information on memory usage.
  • vi:            A text editor
W
  • whereis:   Finds documentation files.
  • who:        Tells you who is logged into your server.
  • whoami:   Tells you your user information.
  • wc:          Print the number of bytes, words, and lines in files
  • which:      Finds the full path for a command.
  • write:       Used to send a message to another user.
  • whois:      Used to query servers for info on.
  • wall:        Writes a message to all logged in users.
X
  • xman:        Graphical interface for man pages.
  • xf86config: Used to configure X.
Z
  • zcat:       Read files that have been compressed with gzip.